Infamous is about 15 hours long.

[forevercloud3000]

I am the type of gamer who spent 23 hours in his first playthrough of MGS4. I also have clocked in over 60hrs in Valkyria Chronicles, and still haven't finished it. So a game that is said to be 10-15 hours is more like 30 for me. Thats completely all right with me for a action adventure game.